There are all types of professions where you risk life and limb for less money and less glory than NFL players.
Also, anyone who thought smashing your head into other people's head while running full speed would not negatively impact your brain... well, it obviously wasn't something you were using in the first place.
Moreover, all of these men had a chance at a free post secondary education. How many of you had that opportunity?
Finally, they can retired and enter the workforce at any time. They are in no way obligated to play until their body breaks down and they have to quit.
I'm sorry, but these NFL players pretty much blame everyone except the primary person responsible.